LONDON, June 30 (Reuters) - Cigarette maker Philip Morris International thinks its iQOS heated tobacco product can make Britain smoke-free in the coming years, an executive said on Friday.

Since iQOS was launched in the UK in December, Philip Morris has found that about 70 percent of people that use it are able to give up conventional cigarettes, Peter Nixon, its UK and Ireland managing director, told BBC Radio. That compares with about 15-20 percent of people who use e-cigarettes, he said.

"It's unprecedented," Nixon told the Today show. "We're very encouraged that products like iQOS are the absolute game changer."

Whereas e-cigarettes use nicotine-laced liquid, IQOS heats tobacco sticks, called Heets, to a high enough temperature to create a vapour but not smoke.

Philip Morris, which has Marlboro cigarettes among its global brands, has applied to U.S. health regulators to have iQOS recognised as having "modified risk" compared with cigarettes.

The relative health benefit of these products was questioned in a study last month, which found that they release chemicals linked to cancer, sometimes in higher concentrations than conventional cigarettes.

British American Tobacco and Japan Tobacco are also selling tobacco-based "vaping" devices, but so far Philip Morris is in the lead.

The company sells about 7 billion Heets a year, which is tiny compared with the 820 billion conventional cigarettes it sells. But Nixon told the BBC that the company hopes to produce 100 billion Heets next year, up from less than 400 million in 2015.

"One day we want to stop selling cigarettes," Nixon said on the programme. "We're moving very fast."

There are still 7.5 million smokers in Britain, Nixon said, and Philip Morris has hired "freelancers" to help to bring that number down. These freelancers act like quitting coaches and can earn 50 pounds ($64.95) from Philip Morris for every person they convert from cigarettes to iQOS.

"With these types of programmes we can get that down to almost zero in coming years," Nixon said. ($1 = 0.7699 pounds) (Reporting by Martinne Geller; Editing by David Goodman)